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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#277747#5139. DFS Order 2zzuqy#WA 2ms20684kbC++112.7kb2023-12-06 22:17:102023-12-06 22:17:10

Judging History

你现在查看的是最新测评结果

  • [2023-12-06 22:17:10]
  • 评测
  • 测评结果:WA
  • 用时:2ms
  • 内存:20684kb
  • [2023-12-06 22:17:10]
  • 提交

answer

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
int read()
{
    int x;cin>>x;
    return x;
}
int mod=998244353;
ll quick(ll a,ll b)
{
	ll t=1;
	while(b)
	{
		if(b&1)
			t=t*a%mod;
		b=b/2;
		a=a*a%mod;
	}
	return t;
}
int n,f[510],siz[510],g[510][510][510],jie[510],ans[510][510],F[510],JIE[510];
int sum[510],cnt[510];
vector<int>e[510];
void dfs(int x,int fa)
{
    f[x]=1;
    siz[x]=1;
    
	for(int i=0;i<e[x].size();i++)
	{
		if(e[x][i]==fa)
		{
			swap(e[x][i],e[x][e[x].size()-1]);
			e[x].resize(e[x].size()-1);
		}
	}
    for(auto y:e[x])
    {
        if(y==fa)
            continue;
        dfs(y,x);
        siz[x]+=siz[y];
        f[x]=1ll*f[x]*f[y]%mod;
        cnt[x]++;
    }
    f[x]=1ll*f[x]*jie[cnt[x]]%mod;
}
queue<pair<int,int>>q;
int vis[510][510];
int main()
{
//    freopen("1.in","r",stdin);
//    freopen("1.out","w",stdout);
    n=read();
    for(int i=1;i<n;i++){
        int x=read(),y=read();
        e[x].push_back(y);
        e[y].push_back(x);
    }
    jie[0]=1;
    for(int i=1;i<=n+1;i++){
        jie[i]=1ll*jie[i-1]*i%mod;
        JIE[i]=quick(jie[i],mod-2);
    }
    dfs(1,0);
    for(int x=n;x>=1;x--)
    {
    	g[x][0][0]=1;
        cnt[x]=0;
        for(auto y:e[x])
        {
            sum[x]+=siz[y];
            cnt[x]++;
            for(int i=sum[x];i>=siz[y];i--)
                for(int j=cnt[x];j>=1;j--)
                   g[x][j][i]=(g[x][j][i]+g[x][j-1][i-siz[y]])%mod;
        }
    }
    q.push({1,1});
    vis[1][1]=1;
    ans[1][1]=1;
    for(int i=1;i<=n;i++)
    	F[i]=quick(f[i],mod-2);
    	
    while(q.size())
    {
    	int x=q.front().first,k=q.front().second;
    	q.pop();
    	int res=ans[x][k];
	    for(auto y:e[x])
	    {
	        for(int i=siz[y];i<=sum[x];i++)
	            for(int j=1;j<=cnt[x];j++)
	               g[x][j][i]=(g[x][j][i]-g[x][j-1][i-siz[y]])%mod;
	        sum[x]-=siz[y];
	        cnt[x]--;
	        for(int i=0;i<=sum[x];i++)
	        {
	            for(int j=0;j<=cnt[x];j++)
	            {
	                if(g[x][j][i]==0)
	                    continue;
					ans[y][k+i+1]+=1ll*res*jie[j]%mod*jie[cnt[x]-j]%mod*g[x][j][i]%mod*f[x]%mod*F[y]%mod*JIE[cnt[x]+1]%mod;
					ans[y][k+i+1]%=mod;
					if(vis[y][k+i+1]==0){
						q.push({y,k+i+1});
						vis[y][k+i+1]=1;
					}
		        }
	        }
	        sum[x]+=siz[y];
	        cnt[x]++;
	        for(int j=cnt[x];j>=1;j--)
	            for(int i=1;i<=sum[x];i++)
	               g[x][j][i]=(g[x][j][i]+g[x][j-1][i-siz[y]])%mod;
	    }
    }
    for(int i=1;i<=n;i++)
    {
        for(int j=1;j<=n;j++)
            cout<<(ans[i][j]*f[i]%mod+mod)%mod<<' ';
        cout<<'\n';
    }
}

Details

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Test #1:

score: 100
Accepted
time: 2ms
memory: 11688kb

input:

5
1 2
1 3
3 4
3 5

output:

4 0 0 0 0 
0 2 0 0 2 
0 2 2 0 0 
0 0 1 2 1 
0 0 1 2 1 

result:

ok 25 numbers

Test #2:

score: 0
Accepted
time: 0ms
memory: 15816kb

input:

10
9 2
9 6
10 5
1 5
1 6
9 3
5 8
4 3
7 9

output:

24 0 0 0 0 0 0 0 0 0 
0 0 0 4 2 2 8 2 2 4 
0 0 0 4 4 4 4 4 4 0 
0 0 0 0 4 4 4 4 4 4 
0 12 0 0 0 0 0 12 0 0 
0 12 0 0 12 0 0 0 0 0 
0 0 0 4 2 2 8 2 2 4 
0 0 6 6 0 0 0 0 6 6 
0 0 12 0 0 12 0 0 0 0 
0 0 6 6 0 0 0 0 6 6 

result:

ok 100 numbers

Test #3:

score: -100
Wrong Answer
time: 0ms
memory: 20684kb

input:

100
18 100
91 87
28 83
11 98
51 52
24 91
72 53
18 19
89 16
77 35
26 25
73 16
96 70
56 44
69 10
63 30
54 95
39 66
58 98
8 71
58 65
74 73
2 64
12 19
32 81
31 54
43 41
84 59
55 75
72 81
59 37
10 94
93 2
64 47
13 32
36 84
28 22
30 28
25 77
47 6
80 52
54 17
23 40
47 88
49 53
65 27
99 59
25 70
91 9
74 1
7...

output:

8388559 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 
0 0 0 0 0 0 0 0 0 0 0 0 0 0 759169026 0 759169026 759169026 0 759169026 0 0 0 759169026 0 759...

result:

wrong answer 115th numbers differ - expected: '62914557', found: '759169026'